In this project, we have studied two pathophysiologically distinct and opposite groups, using advanced non-invasive imaging techniques to establish whether such individuals exhibit microvascular complications and to what extent. Impaired glucose tolerance (IGT) is a clinically silent, altered state of glycemia and a precursor to type 2 diabetes. The presence of IGT is associated with an adverse cardiovascular risk which may be attributable to the early development of microvascular complications, although the risk factors and exact time of onset are unknown. Detailed and robust cardiac studies in IGT cohorts are lacking however recent advances in non-invasive cardiac imaging allow us to detect early and sub- clinical alterations in cardiac structure and function. Using gold standard imaging modalities and state of the art techniques, we have demonstrated that subjects with IGT exhibit a comparable cardiac phenotype to age matched healthy controls. These are the first studies to employ robust, detailed and reproducible methodologies in an IGT cohort and our findings challenge the existing data. In addition to cardiovascular complications, there is also data to support the presence of small fibre neuropathy in subjects with IGT. The diagnosis of small fibre neuropathy often requires invasive skin biopsy. Corneal confocal microscopy (CCM) has emerged as a potential surrogate for skin biopsy in the detection of small fibre neuropathy across a variety of conditions however has yet to be validated in subjects with IGT. We have demonstrated the utility of CCM in detecting small fibre neuropathy in subjects with IGT. Medalists represent a unique group of patients with an extreme duration of Type 1 diabetes and a variable degree of microvascular and macrovascular complications. As such they constitute a special phenotype, which merits further study, especially given the excess cardiovascular mortality in patients with Type 1 diabetes, even in those with good glycemic control. Detailed cardiac studies in medalist cohorts identifying the exact phenotype are lacking. Using gold standard imaging modalities and state of the art techniques, we were able to demonstrate that subjects with type 1 diabetes of extreme duration, remarkably exhibit normal cardiac structure and function.